Dental amalgam mixer



Oct. l0, 1939. I J. A. sAFFlR 2,175,321

DENTAI4J AMALGAM MIXER Filed Dec. 27. 1938 i gwwwf@ Patented oct. 1o,193e UNITED STATES PATENT ori-'lcs 2,175,321 DENTAL AMALGAM MIXER JacobA. safer, chicago, nl. Application December 27, 1938, Serial No. 247,820

3 claims. 'I'his invention relates to improvements in dental amalgammixers.

An object of-this inventionis to provide an v amalgam mixer which is'capable of thoroughly l and properlycombining and mixing the alloy andmercurygenerally in use by dentists for the makingof amalgam as it isemployed to iill cavities in teeth.. v. l

A further ob'ject is the provision of an amallO gam mixer whose actionis such that it is not likely to overtriturate the amalgam as isfrequently the case in present amalgamators, over trituration being veryunsatisfactory because itV has a deleterious effect on the finalexpansion I l of the alloy.

A still further objectbf thisinvention is to provide a means whereby thedentist can, within certain limits, regulate the amount of time hewishes tlie amalgamator to consume in mixing the amalgam. This is animportant point be. cause amalgam sets rather quickly and must be usedalmost immediately after it is prepared; at the: same time the finalsteps in filling most teeth call for sterilization and complete drynesswhich conditions'it is usually impossible to hold for a very extendedperiod. 'Ihe dentist, therefore, strives to have his amalgam mixed andready as near as possible to the time that he has completed his naltoilet of the cavity. Heretofore, without an' assistant to slowlytriturate the amalgam in a mortar while the dentist was working on thecavity, this was nextto impossible. With the present invention thedentist has considerable leeway for, within certain real5 sonablelimits, he can adjust the speed tol consume as much or as little timeas' he requires and will find the process completed just when he hascompleted the necessary preliminary steps.

This invention also enables the dentist to watch the action going Von inthe vamalgamator; previous mechanical amalgamators having been soconstructed as to render it impossible to watch the mass while it isbeing mixed. This visibility is 'often of the greatest importancebecause frequently through an oversight or miscalculation the dentisthas neglected to add sufficient mercury to his mix.- ,Such a mix has tob'e discarded. With applicants device, this deciency can be remediedwhile the apparatus is in operation, B0 more mercury can be added veryeasily, and a.

usable mix result, eliminating the inconvenience' and waste occasionedby anerror which c'ould not previously be rectified. Y

'I'heatt'alnment of the above and further ob- 65 jects of the presentinvention will be apparent from the following specification taken in conjunction with the accompanying'drawing forming a part thereof.

In the drawing:

Figure 1 is a transverse sectional"'view of an d apparatus embodyingthis invention.

Figure 2 is a transverse sectional -view of just the mortar and itsimmediate surroundings in an apparatus showing slightly differentembodiments than those in Figure' 1.

Figure 3 is a similar view to that of Figure 2, I showing still anotherembodiment.

Figure 4 is also a view similar to that of Figure 2 .and showing stillanother embodiment.

L lke parts are designated by the same characl@ ters and symbols ofreference in all the figures.

` In the drawing, 5 designates a casing made of any suitable materialsuch as Bakelite, glass,

or metals of various kinds. It may be of any desired design orconfiguration, the design shown 2c: in Figure 1 being convenientlyillustrative.

In Figure 1J the casing 5 comprises a base, side-walls and a top. On thetop there is an opening in which is set a' glass mortar E, kept in placeby the retainingvmember l. is removable and when set in position foropera,- tion it is so placed that the square indentation I 5 in thebottom of the glass mortar engages .the square head I4 on the upper endof the shaft |2a coming from the motor'l2 which has a sup- .so portingmember 6 which is xed to the casing.

Hinged members I3 and l3a keep the mortar from raising up anddisengaging from his driving means. 'Io remove the mortar these hingedholders are opened up and the mortar can easily 35 be lifted from itspositionand emptied. .ht 9

is a metallic magnetically attractable ball shown here directly abovethe electromagnet iii.

-'fire electromagnet is connected by means of the wires 3 and 3a to aswitch outside of the casing, 4e-

which, when closed energises the magnet and creates a downward pull onthe ball 9.

To operate the amalgamator, the motor i2, which is connected by means of-the wires I2C to a rheostat so that variable speeds are possible, 45 isset in motion at the desired speed. This causes the mortarto revolvewith everything init,vwit,h the exception of the ball 9 which is `beingattracted andheld at the closest point to the magnet.` The ball,however, although remalning at the position mentioned and not varyingmore than -a fraction of a centimeter from that spot does have impartedto ita roll in the direction opposite to the direction of the mortar.

It can be seen, therefore, that when alloy and The mortar 25 Vmercuryare placed in the mortar, 8, and the mortar is made to rotate, the alloyand mercury will be run over by the rolling ball 9 every time and theweight of the ball and pull of the mag-.-

net which can also be made variable by reducing or increasing thecurrent supply to the electromagnet. This factor of magnetic pull cannot be varied where a permanent magnet is employed.

In Figure 2 at I6 is shown a. claw-like scraping member hinged on anadjustable post l1. This is a thin scraping device which is lowered inthe mortar 8 and acts to prohibit the caking of the alloy and mercury onthe bottom of the mortar. The use of this device is optional with thedentist. It is not an absolute requirement vand its chief utility iswhere very large quantities of alloy and mercury are to be amalgamated.In Figure 2, |a is a permanent magnet.

In Figure 3 the mortar 8 rests in a holder 'la which is mounted on aneccentric shaft I9 by means of shaft I8 from the holder 1a. When theshaft I9 is in motion the movement-of the mortar *'I is eccentric andvthe ball 9 is given a rolling motion which is very rapid and the effectof its rolling over alloy and mercury is to cause .mortar 8. In turn theball 9 follows the magnet I0b and by its rotation and pull fromthemagnet causes the amalgamation of the alloyand mercury.

It can be seen that by similar means an electromagnet can be attached toa movable shaft and operated like the magnet illustrated in the aboveparagraph.

I have herein before described the preferred embodiments of thisinvention, but I desire it to be distinctly `understood that I am 4awarethat many changes may be made therein and parts omitted withoutdeparting from the scope of my invention as defined in the subjoinedclaims.

Having thus fully described this invention I claim as new and desire tosecure to myself by Letters Patent of the United States:

1. A device for mixing and triturating, comprising a mortar, atriturating ball loosely disposed within said mortar and beingferro-magnetically responsive, means below the bottom of said mortar forgenerating a magnetic field within at least a portion of the mortarinterior to force said ball tightly against the bottom mortar surface,and means for obtaining relative motion between said mortar on the onehand, and said 'ball and magnetic field generating means -on the otherhand, said ballv being adapted to be maintained within the generatedfield and roll with respect to the mortar surface and be pressed tightlyagainst said surface-to -triturate any material withinv said mortar.

2. A device for mixing and triturating, com l priaing` amortar, atriturating ball loosely disposed within the mortar and beingferro-magnetically responsive, means below the bottom of said mortar forgenerating Va magnetic field within at least a portion` of the mortarinterior to force said ball tightly against said mortar bottom, ascraping member depending in said mortar and normally/disposed at aregion remote from 'said ball, and means for obtaining relative motionbetween said mortar on the one hand and said ball and magnetic eldgenerating means and scraper on the other hand, said ball being adaptedto be maintained within the magnetic field and roll lwith respect tothemortar surface and be tightly pressed against ysaid surface to triturateany material within said mortar,- and said scraper being adapted tobreak up any agglomerations of material within said mortar. v

3. The structure of claim 1, wherein the mortar travels Awith respecttothe ball and magnetic fleld generating means in a circle eccentric with

